Leukocytes (PMN) have been shown to use laminin preferentially to adhere to type IV-collagenous matrices. We now report that these cells contain laminin receptors that bind labelled laminin with high affinity (Kd = 6.16 x nM/L). An estimated 36,000 binding sites per cell are present. Monoclonal antibodies to the receptor inhibit the chemotactic response of PMN to peptide attractants. These findings suggest a major role for the laminin receptor in PMN attachment and migration. These characteristics are quite similar to those of highly metastatic tumor cells.